Method and device for vein ablation

ABSTRACT

A method for collapsing a target vein in a patient. The method comprises providing an intravascular irritation element having a plurality of mechanical irritating objects, inserting the intravascular irritation element into a venous lumen of a target vein, and irritating the target vein by moving the plurality of mechanical irritating objects in contact with the inner surface thereof, thereby triggering a collapse of the target vein.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.12/920,335 filed on Aug. 31, 2010, which is a National Phase of PCTPatent Application No. PCT/IL2009/000241 having International FilingDate of Mar. 2, 2009, which claims the benefit of U.S. ProvisionalPatent Application No. 61/032,978 filed on Mar. 2, 2008.

The contents of the above Applications are all incorporated herein byreference.

FIELD AND BACKGROUND OF THE INVENTION

The present invention, in some embodiments thereof, relates to methodand device for vein treatment and, more particularly, but notexclusively, to a method and a device for vein ablation.

Varicose veins occur when weak veins near the surface of the legstretch, bulge, and twist. Varicose veins can be visible through theskin. In varicose veins, the valves arc malfunctioning or destroyed sothat the veins balloon at the lower ends. This condition can beparticularly pronounced in certain leg veins. Various methods have beendeveloped for performing varicose vein ablation.

For example, one commonly used treatment is known as stripping surgicalprocedure. In a conventional stripping for the treatment of varicoseveins, two incisions are made in a vein, one at the ankle and one at thegroin. An elongate stripper instrument is then inserted through theankle incision and passed through the vein to the groin. At the groin, acup is attached to the distal end of the stripper. Subsequently, thestripper is pulled down the leg so that the cup rips out the vein. Inthis procedure, other veins connecting to the varicose vein are torn.

Another commonly used treatment is based on laser, electric orradio-frequency energy. When laser is used, bursts of radiofrequency orlaser energy are sent through a catheter; the resulting heatintentionally destroys vein wall tissues along the length of the vein.

Other methods have been developed during the years. For example, U.S.Pat. No. 6,402,745 issued on Jun. 11, 202 describes an intravenoussurgical instrument comprises an inner shaft or post and an outersheath. A spring-tail or whip-like electrode is disposed at a distal endof the inner post, substantially in a sagittal plane, or oneperpendicular to a longitudinal axis of the shaft. Following aninsertion into a human vein or other circulatory vessel the distal endof the shaft is protruded from the sheath; thereafter sheath, post andelectrode are simultaneously withdrawn from the vein, with a relativerotatory motion being imparted to the electrode. A current flow ispreferably simultaneously imposed across the electrode into an innersurface of the surrounding vessel, facilitating a damaging of the vesselinner surface and a collapse of the vessel. This description appliesprimarily to veins, which may be drained of blood prior to a start of acollapsing procedure; for use in arteries a modified embodiment isdisclosed employing a compound construction electrode tip whichfacilitates a limiting of current flow to a region of direct electrodecontact with a circulatory vessel wall, and a reduction of straycurrents conduction into the blood.

Another example is described in U.S. Pat. No. 7,326,206, issued on Feb.5, 208, that describes brush electrode catheter and a method for usingthe brush electrode catheter for tissue ablation. The brush electrodecatheter comprises a plurality of flexible filaments or bristles forapplying ablative energy (e.g., RF energy) to target tissue during theformation of spot or continuous linear lesions. Interstitial spaces aredefined among the filaments of the brush electrode, and the interstitialspaces are adapted to direct conductive or nonconductive fluid, whenpresent, toward the distal ends of the brush filaments. The brushelectrode facilitates electrode-tissue contact in target tissue havingflat or contoured surfaces. The flexible filaments may be selectivelytrimmed to give a desired tip configuration or a desired standoffdistance between the tissue and the conductive filaments in the brushelectrode. Also, the filaments may be grouped into clusters. Ashielded-tip brush electrode, including a flexible boot, is alsodisclosed.

SUMMARY OF THE INVENTION

According to some embodiments of the present invention there is provideda method for collapsing a target vein in a patient. The method comprisesproviding an intravascular irritation element having a plurality ofmechanical irritating objects, inserting the intravascular irritationelement into a venous lumen of a target vein, and irritating the targetvein by moving the intravascular irritation element in contact with aninner surface thereof so that a collapse of the target vein istriggered.

Optionally, the target vein is the saphenous vein.

Optionally, the inserting comprises inserting the intravascularirritation element in a narrowed configuration and the irritatingcomprising expanding the intravascular irritation element in the venouslumen so that the plurality of mechanical irritating objects contact theinner surface.

Optionally, the intravascular irritation element comprising a shapememory element having a regainable geometry, wherein the providingcomprises providing the intravascular irritation element in a collapsedstate and the irritating comprises allowing the shape memory element toexpand toward the regainable geometry in the venous lumen.

Optionally, the irritating comprises rotating the intravascularirritation element approximately around a longitudinal axis of thetarget lumen.

More optionally, the rotating is performed simultaneously with at leastone of pushing and pulling the intravascular irritation element alongthe longitudinal axis.

Optionally, the irritating comprises maneuvering the intravascularirritation element so that at least one of the mechanical irritatingobjects is brushed against the inner surface in a helical pattern.

Optionally, the inserting comprises releasing a sclerosing agent inproximity to the inner surface.

Optionally, the inserting comprises withdrawing blood in proximity tothe inner surface.

According to some embodiments of the present invention there is providedan intrabody device for collapsing a target vein in a patient. Theintrabody device comprises a shaft being insertable into a venous lumenof a target vein and an intravascular irritation element affixed at adistal end of the shaft and having a plurality of mechanical irritatingobjects. The intravascular irritation element is sized and shaped to bemoved in the venous lumen so that the plurality of mechanical irritatingobjects are in contact with an inner surface of the target vein.

Optionally, the intravascular irritation element is a wire and theplurality of mechanical irritating objects are plurality of bristlesprotruded therefrom.

Optionally, the wire being made of a memory shape material.

Optionally, the intrabody device further comprises a sheath covering atleast the distal end, the intravascular irritation element having acollapsed state for inserting the intravascular irritation element intothe sheath and an expanded state for brushing against the inner surface.

Optionally, the intravascular irritation element is a flexible meshwoven from a first wire made of a shape memory material and a secondwire having the plurality of mechanical irritating objects affixedthereto.

Optionally, the intrabody device further comprises a controller forsimultaneously rotating the intravascular irritation elementapproximately around a longitudinal axis of the target lumen and atleast one of pushing the intravascular irritation element along thelongitudinal axis and pulling the intravascular irritation element alongthe longitudinal axis.

Optionally, the intrabody device further comprises an extraction channelpositioned along the shaft and configured for withdrawing blood inproximity to the intravascular irritation element.

More optionally, the extraction channel is configured for performing thewithdrawing while the intravascular irritation element is maneuvered.

Optionally, the intrabody device further comprises an ejection channelpositioned along the shaft and configured for releasing a medicalsubstance in proximity to the intravascular irritation element.

More optionally, the medical substance comprises a sclerosing agent.

More optionally, the ejection channel is configured for performing thereleasing while the intravascular irritation element is maneuvered.

More optionally, the ejection channel is configured for performing thereleasing after the intravascular irritation element being maneuvered.

More optionally, the ejection channel is configured for performing thereleasing before the intravascular irritation element being maneuvered.

Optionally, the intrabody device further comprises an expandable filterelement affixed at a distal end of the intravascular irritation elementand configured for filtering blood during the intravascular irritationelement being maneuvered in the venous lumen.

According to some embodiments of the present invention there is provideda kit for collapsing a target vein in a patient. The kit comprises aplurality of detachable intravascular irritation element s eachconfigured for moving in contact with an inner surface of a target veinhaving at least one different anatomical characteristic and a shaftconfigured for detachably coupling at least one of the plurality ofdetachable intravascular irritation elements and inserting the coupleddetachable intravascular irritation element into a venous lumen.

Unless otherwise defined, all technical and/or scientific terms usedherein have the same meaning as commonly understood by one of ordinaryskill in the art to which the invention pertains. Although methods andmaterials similar or equivalent to those described herein can be used inthe practice or testing of embodiments of the invention, exemplarymethods and/or materials are described below. In case of conflict, thepatent specification, including definitions, will control. In addition,the materials, methods, and examples are illustrative only and are notintended to be necessarily limiting.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Some embodiments of the invention are herein described, by way ofexample only, with reference to the accompanying drawings. With specificreference now to the drawings in detail, it is stressed that theparticulars shown are by way of example and for purposes of illustrativediscussion of embodiments of the invention. In this regard, thedescription taken with the drawings makes apparent to those skilled inthe art how embodiments of the invention may be practiced.

In the drawings:

FIG. 1 is a flowchart of a method for collapsing a target vein in apatient for using mechanical irritating objects, according to someembodiments of the present invention;

FIG. 2 is a schematic illustration of a distal tip of an exemplarymechanical vein elimination device having a plurality of mechanicalirritating objects, according to some embodiments of the presentinvention;

FIG. 3 is a schematic illustration of an intravascular irritationelement having a mechanism for releasing a medical substance a beforethe venous wall is irritated by the intravascular irritation element,according to some embodiments of the present invention;

FIG. 4 is a schematic illustration of a mechanical vein eliminationdevice with a mechanism for releasing a medical substance after thevenous wall is irritated by the intravascular irritation element,according to some embodiments of the present invention;

FIG. 5 is a schematic illustration of a tip of a mechanical veinelimination device having an intravascular irritation element that ispositioned on an expandable structure, according to some embodiments ofthe present invention;

FIG. 6A is a schematic illustration of another intravascular irritationelement having an expandable structure, according to some embodiments ofthe present invention;

FIG. 6B is a schematic illustration of a wire having bristles which maybe used for constructing an intravascular irritation element, accordingto some embodiments of the present invention;

FIG. 7 is a schematic illustration of a tip of a mechanical veinelimination device having an intravascular irritation element that ispositioned on an expandable structure and a plurality of inlets andoutlets for releasing medical substance and withdrawing blood, accordingto some embodiments of the present invention;

FIG. 8 is a schematic illustration of a mechanical vein eliminationdevice having a filtering element, according to some embodiments of thepresent invention;

FIG. 9A is a schematic illustration of a mechanical vein eliminationdevice with an intravascular irritation element that includes anexpandable mesh, according to some embodiments of the present invention;and

FIG. 9B is an intravascular irritation element which is constructed froma woven mesh, according to some embodiments of the present invention.

DESCRIPTION OF SPECIFIC EMBODIMENTS OF THE INVENTION

The present invention, in some embodiments thereof, relates to methodand device for vein treatment and, more particularly, but notexclusively, to a method and a device for vein ablation.

According to some embodiments of the present invention there is providedan intrabody device and a method for collapsing one or more targetveins, such as the saphenous vein, in a patient. The method and thedevice are based on an intravascular irritation element, such as a wireor a mesh of wires, having a plurality of mechanical irritating objects,such as bristles or pins. In use, the intravascular irritation elementis inserted into a venous lumen of a target vein and maneuvered by thecaretaker, automatically and/or manually, so that an inner surface ofthe target vein, such as the intima, is irritated by the plurality ofmechanical irritating objects which are optionally brushed against it.Such brushing damages the inner surface and therefore triggers acollapse of the target vein, preferably permanently.

Optionally, the device is designed to release one or more medicalsubstances into the venous lumen, in proximity to the inner surface,before, during, and/or after the irritation. In such an embodiment, asclerosing agent may be released into the venous lumen, in proximity tothe inner surface, advancing the collapse of the target vein.

Additionally or alternatively, the device is designed to withdraw bloodand/or debris from the venous lumen, in proximity to the inner surface,before, during, and/or after the irritating. In such an embodiment,withdrawing of blood may expedite the collapsing of the target veinand/or prevent from debris and/or the released medical substance fromflowing away from the treated area.

Optionally, the device further comprises a filtering element, optionallyexpandable, for filtering blood in the treated area. In such anembodiment, debris and/or medical substances released during thetreatment may be filtered and extracted from the body.

Before explaining at least one embodiment of the invention in detail, itis to be understood that the invention is not necessarily limited in itsapplication to the details of construction and the arrangement of thecomponents and/or methods set forth in the following description and/orillustrated in the drawings and/or the Examples. The invention iscapable of other embodiments or of being practiced or carried out invarious ways.

Reference is now made to FIG. 1, which is a schematic illustration of amethod for collapsing, preferably permanently, a target vein in apatient using mechanical irritating objects, according to someembodiments of the present invention. As used herein, the target veinmay be a perforator vein, a spider vein, a varicose vein, hemroids,varicocele and/or a saphenous vein which is selected by a caretaker forreceiving vein ablation treatment. The target vein may be any vein whichdesignated for elimination in any medical and/or cosmetic procedure. Asshown at 101, the method is based on an intravascular irritation elementhaving a plurality of mechanical irritating objects. Optionally, theintravascular irritation element is an expandable element having aplurality of mechanical irritating objects, such as bristles, pins,wires, studs, anchors, knives, filers, hooks, and/or any type ofscratchers. For example, the mechanical irritating object is a bristle,optionally sharpened, having a length between 0.05 mm and 0.4 mm, forexample 0.1 mm. Optionally, the intravascular irritation element is awire and the mechanical irritating objects bristles, which are affixedthereon, in a variety of directions and combinations in relation to theintravascular irritation element longitudinal axis, for example asdepicted in FIG. 6B. Optionally, mechanical irritating objects areinclined in two opposing directions, optionally toward the two opposingtips of the intravascular irritation element. In such an embodiment, theirritation is performed when the mechanical irritating objects arepulled and/or pushed. Optionally, the treatment is performed bymaneuvering the intravascular irritation element back and forth alongthe target vein. The intravascular irritation element is affixed at adistal end of a shaft that is designed to be inserted into a lumen of atarget vein. For brevity a device comprising at least a shaft and anintravascular irritation element may be referred to herein as amechanical vein elimination device.

Reference is now also made to FIG. 2, which is a schematic illustrationof a distal tip 20 of an exemplary mechanical vein elimination device 20having a plurality of mechanical irritating objects 24, according tosome embodiments of the present invention. The mechanical veinelimination device 20 comprises a shaft 21 that is optionally encircledby an outer sheath, such as a common catheter sheath. In such anembodiment, the mechanical vein elimination device 20 further comprisesa controller, such as a double syringe controller (not shown), forseparately controlling the shaft 21 and the sheath 22 along alongitudinal axis which is parallel or substantially parallel to thelongitudinal axis of the shaft 21.

The exemplary mechanical vein elimination device 20 further comprises anintravascular irritation element 23 which is affixed, detachably orintegrally, to the distal end of the shaft 21. As described above, theintravascular irritation element 23 has a plurality of mechanicalirritating objects 24, such as pins, wires, studs and/or any otherscratchers arranged to abrade, scratch, peel, or catch, of the innersurface, or intima, of the target vein. The target vein may be inproximity to a venous branch, for example at the inner surface ofvaricose vein segments in proximity to perforators, such as the midthigh (hunterian) perforator, the popliteal vein, the Dodd's perforator,and the Boyd's perforator. The intravascular irritation element 23 isoptionally sized and shaped, for example as shown in FIG. 2, to allowthe plurality of mechanical irritating objects 24 to contact the innersurface of a target vein 26.

Optionally, the intravascular irritation element 23 has a collapsedstate, in which it is narrowed for allowing the insertion thereof intothe venous lumen and an expanded state for establishing a contact withthe inner surface of the target vein 26, as described above. Optionally,the intravascular irritation element 23 is made from a shape memoryalloy (SMA), also known as a smart alloy, a memory metal, and/or musclewire, such as Nickel Titanium (NiTi). In such an embodiment, theintravascular irritation element 23 is designed to switch from thecollapsed state to the expanded state by regaining a geometry that issized to at least contact the inner surface of a target vein, such asthe great saphenous vein and/or the small saphenous vein. The ability toregain the geometry allows narrowing the intravascular irritationelement 23 while the distal end of the mechanical vein eliminationdevice 20 is positioned in the venous lumen of the target vein. Forexample, the intravascular irritation element 23 may be held in anarrowed configuration by the inner walls of the sheath 22.

As shown at 102, after the mechanical vein elimination device 20 isprovided, as shown at 101, the distal end of the mechanical veinelimination device 20 is inserted with the intravascular irritationelement 23, optionally in a collapsed state, into a venous lumen of atarget vein. Optionally, the insertion is guided using ultrasound probe,according to a commonly known intravascular ultrasound process.

As shown at 103, when the intravascular irritation element 23 is intarget vein, and optionally switched to an expanded state, themechanical irritating objects are positioned to move in contact with theinner surface of the venous walls. Optionally, the mechanical irritatingobjects are brushed against the inner surface of the venous walls duringthis movement. As used herein brushing means brushing, rubbing,scribing, scratching and/or otherwise irritating the inner surface of avein. Optionally, the movement in contact is performed when theintravascular irritation element 23 is withdrawn from the vein,optionally in a pulling operation. The movement in contact is optionallyperformed by rotating the intravascular irritation element 23, forexample around the longitudinal axis of the shaft 21, which is parallel,optionally in an overlapping manner, to the longitudinal axis of thetarget vein. Optionally, the intravascular irritation element 23 issimultaneously rotated and pulled or pushed. In such a manner, themovement forms a helical pattern on the inner surface of the targetvein. In such an embodiment, the inner surface may be brushed in ahelical pattern.

The movement of the mechanical irritating objects in contact with theinner surface scratches, irritates, scribes, peels, catches, and/orotherwise damages the venous walls, for example the intima thereof. Asshown at 104, such damage causes the vein to permanently collapse, forexample due to the clotting and/or the coagulation of the area. Inaddition, the damage causes the forming of a scar tissue in the treatedarea.

Optionally, after the intravascular irritation element 23 is insertedinto the target vein, the treatment is provided segment by segment. Eachsegment may be between 3 and 12 centimeters (cm), for example accordingto the decision of the caretaker. For example, if the treatment includesejection of medical substances and/or withdrawing of blood, as furtherdescribed below, the maneuvering of the intravascular irritation element23 and the withdrawing and/or the ejection are performed in a number ofintervals, optionally consecutive, wherein during each interval adifferent segment is treated.

It should be noted that in such an embodiment, the vein is eliminated,for example permanently collapsed, without using sclerosing agents,foreign chemicals electromagnetic (EM) radiation, heating and/orfreezing techniques and/or laser energy.

As no chemicals are used, the likelihood of discoloration orhyper-pigmentation of the skin in proximity to the treated area isreduced and/or eliminated.

It should be noted that as the treatment described herein may notinvolve using radiating, heating and/or freezing. As such the treatmentmay be provided as a complementary treatment to area which is sensitiveto radiating, heating and/or freezing. In such a manner, some targetveins or segments thereof may be treated with radiating, heating and/orfreezing while others are treated as described herein.

It should be noted that as the treatment described herein may notinclude using sclerosing agents. As such, the treatment may be providedto patients which are sestive or allergic to the sclerosing agents.

According to some embodiments of the present invention, there isprovided a kit having a shaft 21 and a plurality of detachableintravascular irritation elements. Optionally, each detachableintravascular irritation element is sized and shaped according to theanatomical characteristics of different veins, for example according tothe diameter of each vein and/or the presence and/or absence ofrelatively large venous valves. For example, one detachableintravascular irritation element may be sized and shaped according tothe diameter of the great saphenous vein and the other according to thediameter of small saphenous vein. Optionally, each detachableintravascular irritation element 23 is designed for damaging the venouswalls, for example the intima thereof, in a different pattern and/or toa different extent. In such a manner, the caretaker may select amonglow, moderate and/or high levels of damaging the venous walls, fromcausing minor irritation through an inner peeling or even a veinstripping. For instance, the mechanical irritating objects 24 of eachdetachable intravascular irritation element 23 may have a differentdegree of sharpness, a different level of strength, a different degreeof flexibility, and/or a different degree angle in relation to thecentral axis of the intravascular irritation element 23. In such amanner, the caretaker may adjust the pattern to the medical condition ofthe patient. For example if the patient takes blood thinner, such asplavix™, a detachable intravascular irritation element 23 that causesless damage is selected, as the clotting pace is relatively slow.

Optionally, the mechanical vein elimination device 20 further comprisesan extraction channel for withdrawing blood and/or debris which isreleased when the venous walls are damaged. The withdrawing is performedbefore and/or when the mechanical irritating objects irritates thevenous walls, for example by being brushed against them. Optionally, theextraction channel is positioned along the shaft 21. Optionally, theextraction channel has a suction opening 25 that is directed toward theintravascular irritation element 23. Optionally, the extraction channelis the lumen between the shaft 21 and the sheath 22 and/or positioned inthis lumen. Optionally, the withdrawing of blood from the target veindecreases the volume of blood in the target vein and enabling thereleased sclerosing agents or drugs, as described below.

Additionally or alternatively, the mechanical vein elimination device 20further comprises an ejection channel for releasing a medical substancecomprising one or more of the following: a sclerosing agent, such assodium tetradecyl sulfate (STS), polydocanol, and bleomycin, a drug, amedical component, a filling, such as hyaluronic acid (HA) secretion andcollagen, a medical agent and/or any combination thereof. The medicalsubstance is released before, during, and/or after the mechanicalirritating objects irritate the venous walls. Optionally, the ejectionchannel is positioned along the shaft 21. Optionally, the ejectionchannel has a release opening 25 that is directed toward theintravascular irritation element 23. Optionally, the extraction channelis the lumen between the shaft 21 and the sheath 22 and/or positioned inthis lumen. Such an ejection channel enables delivery of the medicalsubstance into the lumen in proximity to the damaged venous walls.Optionally, the released medical substance is a sclerosing agent that isdesigned to shrink the target vein. As the venous walls are damaged bythe mechanical irritating object, the sclerosing agent permeability rateis increased. The sclerosing agent penetrates the injured intima,expedite and/or facilitate the occluding thereof. Optionally, thereleasing and the withdrawing are synchronized in a manner that allowswithdrawing the medical substance after the administration thereof, forexample as described in International Patent Application No.PCT/IL209/000197 filed on Feb. 19, 209, which is incorporated herein byreference.

It should be noted that as venous walls are irritated during thetreatment, the amount and/or the concentration of the sclerosing agentmay be relatively low in relation to the amount and/or the concentrationof the sclerosing agent which are used in a common sclerotherapyprocedure. For example, the concentration of the sclerosing agent may beless than the concentration that is used in standard treatments, forexample less than 5%, 3% and 1%. Furthermore, in typical sclerotherapyprocedures, the vein valve areas pose a greater challenge to ablate asthe venous walls are thicker and bulkier than other areas. As such, theamount and/or concentration which are used are typically higher. As thescratching damages the vein valve areas, the amount and/or concentrationof sclerosing agents which are used for the ablation of the target veinin these areas may be reduced.

The ejection channel is connected to an ejection force source, such as apiston, for applying an ejection force for conducting the medicalsubstance through the channels. The extraction channel is connected to asuction force source, such as a piston, for applying a suction force forwithdrawing blood and/or debris from the venous lumen through theextraction channel.

Optionally, the ejection channel and/or a number of additional ejectionchannels which are positioned in parallel to the ejection channel may beused for administering additional medical substances in combination tothe medical substance which is administered by the ejection channel.

Reference is now also made to FIG. 3, which is a schematic illustrationof an intravascular irritation element 23 having a mechanism forreleasing a medical substance 615 before the venous wall is irritated bythe intravascular irritation element 23, according to some embodimentsof the present invention. The intravascular irritation element 23 isoptionally conducted in a catheter deliver that comprises the shaft 21in a sheath 130.

In such an embodiment, the ejection channel may be integrated into theshaft 21. For example, the shaft 21 may be hollow, having a lumen thatfunctions as an ejection channel. In such a manner, the ejection channelmay release the medical substance directly via the intravascularirritation element 23.

In such an embodiment, the intravascular irritation element 23 has oneor more releasing areas 615, such as a plurality of outlets, such asapertures and/or nozzles, and a vein scratching area 602 that includesthe mechanical irritating objects. As shown in FIG. 3, in use, the veinscratching area 602 is closer to the distal point of mechanical veinelimination device 20, and the releasing area 615 is closer to theproximal side of the mechanical vein elimination device 20, or furtherupstream in the vein, so that when releasing or extracting device 20from the target vein, the sclerosing materials may be applied to an areaof the vein before the irritating the vein scratching area 602 againstthe venous walls takes place. In such a manner, when treatment isperformed by removing or pulling the mechanical vein elimination device20 out of the vein, for example against the direction of the blood flow,the medical substance first interact with the venous wall, andsubsequently, upon pulling the intravascular irritation element 23through the treated area, the intravascular irritation element 23damages the venous wall.

Reference is now made to FIG. 4, which is a schematic illustration of amechanical vein elimination device 230 with a mechanism for releasing amedical substance after the venous wall is brushed with the a veinscratching area 234 of the intravascular irritation element 23,according to some embodiments of the present invention. Similarly toFIG. 3, the mechanical vein elimination device 230 comprises veinscratching area 234 and releasing area 232. However, in FIG. 4, thematerial releasing area 232 is positioned at the distal end of theintravascular irritation element 23, downstream in relation to themedical material releasing area 232. In such a manner, when treatment isperformed by removing or pulling the mechanical vein elimination device230 from the venous lumen, for example against the direction of theblood flow, the mechanical vein elimination device 230 scratches thevenous wall, thereby causing bleeding, coagulation, and scarring theselected area. Then, upon pulling the mechanical vein elimination device230 through the treated area, the medical substance is released throughthe holes in material releasing area 232, thereby interact with thedamaged venous wall.

Reference is now made to FIG. 5, which is a schematic illustration of atip of a mechanical vein elimination device 299 having an intravascularirritation element 306 that is positioned on an expandable structure305, referred to herein cumulatively as an expandable intravascularirritation element 300, according to some embodiments of the presentinvention. As described above, the intravascular irritation element 300has a collapsed state, in which it is narrowed for allowing theinsertion thereof into the venous lumen and an expanded state forestablishing a contact with the inner surface of the target vein 26, asdescribed above. The ability to narrow the expandable intravascularirritation element 300 allows delivering it to a target location using astandard introductory catheter 302 or any other suitable deliverymechanism. The mechanical vein elimination device 300 may includemultiple expandable and/or flexible mechanical irritating objects 305 onthe intravascular irritation element 306. Optionally, the intravascularirritation element 306 is wire and the mechanical irritating objects 305are bristles which are connected thereto. The wire is optionallyspirally or helically arranged on an expandable structure. The flexiblemechanical irritating objects 305 may be constructed from SMA orattached to a structure that is constructed from an SMA or a springloaded materials. In use, the intravascular irritation element 300expands toward the venous walls when released from the catheter 302.

In some embodiments mechanical irritating objects 24 may be engraved,etched or cut into one or more flexible arms and/or wires which are setto form an expandable structure, as shown by numeral 342 of FIG. 6A.FIG. 6B is a close up of an exemplary wire. Optionally, coarse elementsmay be stuck or melted onto the arms, to provide a rough or coursesurface that can scratch the vein walls/intima.

In other embodiments, the flexible arms and/or wires with the mechanicalirritating objects 305 are attached to or positioned above a flexiblestructure, optionally made from SMA wires. Optionally, the mechanicalirritating objects 24 are flexible pins which are perpendicular to theshaft. In such an embodiment, the pins may be bended to diminish thediameter of the intravascular irritation element 23, for example bypulling the shaft 21 into a sheath that encircle it, for example asshown in FIG. 2.

The flexibility and/or expandability of the mechanical irritatingobjects 24 and/or of a structure that supports them allow scratching acurved inner surface of a target vein. The mechanical irritating objects24 are diverted toward the venous walls and bended by the curves of theinner surface.

Optionally, the mechanical irritating objects 24 are arranged in ahelical or a spiral structure. For example, the mechanical irritatingobjects 24 may be attached, engraved, etched and/or cut in a wire thatis positioned in a helical manner on an expandable structure, as shownin FIG. 5. Such a structure assures that a substantially inner surfaceof the venous wall is scratched when the intravascular irritationelement 23 is pulled and/or pushed along the target vein. Optionally, inuse, the intravascular irritation element 23 is designed to regain to ageometry that is wider than the venous lumen of the target vein. In sucha manner, when maneuvered, the intravascular irritation element iscontinually bended against the vein passage surface which limits itsexpanding. In such manner, narrow and wide vein areas are scratched, forexample a narrow vein valve area and a straight inner venous surface maybe scratched. Such a treatment allows avoiding unintentional veinperforation or stripping and other undesirable outcomes by limiting thepenetration of the device into the intima. The mechanical irritatingobjects 24 lengths and/or sharpness is designed to avoid excessivedamage and/or tear of the target vein.

Optionally, as described above, the intravascular irritation element 23may be rotated during the pulling and/or the pushing thereof in thevenous lumen. In such a manner, a helical scratching pattern is formedand the area of the inner surface of the venous wall that is scratchedis increased. In such an embodiment, the likelihood of successfullyablating the target vein is respectively increased. Reference is nowmade to FIG. 7, which is a schematic illustration of a mechanical veinelimination device 320, according to some embodiments of the presentinvention. As depicted in FIGS. 3 and 5, FIG. 7 depicts a mechanicalvein elimination device 320 with a sheath 302, a shaft 21, and anintravascular irritation element 300 with an expandable structure 305.Similarly to the described above, the mechanical vein elimination device320 comprises an ejection channel 326 that is integrated into the shaft21 and an extraction channel 327 at the lumen between the sheath 302 andthe shaft 21. The ejection channel 326 comprises a plurality of outlets325 which are directed toward the wall of the venous lumen. Theextraction channel 327 comprises a plurality of outlets 328 which aredirected toward the wall of the venous lumen.

Reference is now made to FIG. 8, which is a schematic illustration of amechanical vein elimination device 320 having a filtering element 365for preventing from debris and/or other materials from escaping the areaof the treatment and flowing upstream in the vein, according to someembodiments of the present invention. As depicted in FIGS. 3 and 5, FIG.8 depicts a mechanical vein elimination device 320 with a deliverycatheter 363 that includes the sheath 302 and the shaft 21 and with theintravascular irritation element 300. However, in FIG. 8, the mechanicalirritating objects 360 are engraved, etched or cut into one or moreflexible arms which are positioned in parallel to the central axis ofthe shaft. In addition, FIG. 8 depicts the filtering element 365.Optionally, the filtering element 365 is designed to capture the debristhat is formed by the irritating of the venous walls with the mechanicalirritating objects.

The filtering element 365 may be used for blocking, optionallysubstantially completely, the target vein. For example, the filteringelement 365 may be a stent-like mechanism to expand so as to spreadacross the entire vein circumference, to be substantially impermeablefor undesired objects and/or debris. The filtering element 365 may beautomatically deployed at the distal end of the mechanical veinelimination device 320, upon releasing the intravascular irritationelement 300 from the delivery catheter 363. The filtering element 365may be substantially impermeable, or may be permeable to certaincontents yet impermeable to other contents. For example, the filteringelement 365 may allow blood to flow downstream while it filters clotsand/or other solid objects having a predefined diameter therefrom. Thefiltering element 365 may be used for preventing debris and/or clotsfrom flowing downstream before, during and/or after the irritating ofthe venous walls. Optionally, the mechanical vein elimination device 320has an ejection channel, for example as described above. In such anembodiment, the filtering element 365 may additionally or alternativelyfilter medical substances which are released by the ejection channel.

Reference is now made to FIG. 9A, which is a schematic illustration of amechanical vein elimination device 380 with an intravascular irritationelement that includes an expandable mesh 385, according to someembodiments of the present invention. As depicted in FIGS. 3 and 5, themechanical vein elimination device 380 of FIG. 9A has a deliverycatheter that includes the sheath 302, the shaft 21, and anintravascular irritation element 385. However, as depicted in FIG. 9A,the mechanical vein elimination device 380 includes a plurality ofoutlets 379 for releasing a medical substance substantiallyperpendicular to the mechanical irritating objects and the intravascularirritation element 385 thereof comprises a flexible mesh designed toexpand so as to contact and scratch the venous walls. Optionally, themesh 385 is constructed by weaving wires. Optionally, as shown at FIG.9B, one or more of the wires are memory shape wires, such as an SMA wire386, for allowing the expanding the intravascular irritation element 385so as to contact and scratch the venous walls and one or more of thewires includes mechanical irritating objects 387, for example coarseand/or jagged wires. When the mechanical vein elimination device 380 isdeployed in a venous lumen, the mesh 385 expands to contact the venouswalls. Optionally the mesh 385 is made of one or more memory shape wireswhich are designed to regain a shape of a cylinder having a diameterthat is greater than the diameter of the venous lumen. Thus, in use, themesh 385 is pushed toward the inner surface of the venous walls, even ifthe surface features of the venous walls are curved and/or otherwise nonlinear. Optionally, the mesh has holes for releasing medicinalsubstances, such as sclerosing agents, from the plurality of outlets379.

It is expected that during the life of a patent maturing from thisapplication many relevant methods and devices will be developed and thescope of the term a shape memory material, a catheter, and ultrasoundguiding is intended to include all such new technologies a priori.

As used herein the term “about” refers to ±10.

The terms “comprises”, “comprising”, “includes”, “including”, “having”and their conjugates mean “including but not limited to”. This termencompasses the terms “consisting of” and “consisting essentially of”.

The phrase “consisting essentially of” means that the composition ormethod may include additional ingredients and/or steps, but only if theadditional ingredients and/or steps do not materially alter the basicand novel characteristics of the claimed composition or method.

As used herein, the singular form “a”, “an” and “the” include pluralreferences unless the context clearly dictates otherwise. For example,the term “a compound” or “at least one compound” may include a pluralityof compounds, including mixtures thereof.

The word “exemplary” is used herein to mean “serving as an example,instance or illustration”. Any embodiment described as “exemplary” isnot necessarily to be construed as preferred or advantageous over otherembodiments and/or to exclude the incorporation of features from otherembodiments.

The word “optionally” is used herein to mean “is provided in someembodiments and not provided in other embodiments”. Any particularembodiment of the invention may include a plurality of “optional”features unless such features conflict.

Throughout this application, various embodiments of this invention maybe presented in a range format. It should be understood that thedescription in range format is merely for convenience and brevity andshould not be construed as an inflexible limitation on the scope of theinvention. Accordingly, the description of a range should be consideredto have specifically disclosed all the possible subranges as well asindividual numerical values within that range. For example, descriptionof a range such as from 1 to 6 should be considered to have specificallydisclosed subranges such as from 1 to 3, from 1 to 4, from 1 to 5, from2 to 4, from 2 to 6, from 3 to 6 etc., as well as individual numberswithin that range, for example, 1, 2, 3, 4, 5, and 6. This appliesregardless of the breadth of the range.

Whenever a numerical range is indicated herein, it is meant to includeany cited numeral (fractional or integral) within the indicated range.The phrases “ranging/ranges between” a first indicate number and asecond indicate number and “ranging/ranges from” a first indicate number“to” a second indicate number are used herein interchangeably and aremeant to include the first and second indicated numbers and all thefractional and integral numerals therebetween.

As used herein the term “method” refers to manners, means, techniquesand procedures for accomplishing a given task including, but not limitedto, those manners, means, techniques and procedures either known to, orreadily developed from known manners, means, techniques and proceduresby practitioners of the chemical, pharmacological, biological,biochemical and medical arts.

As used herein, the term “treating” includes abrogating, substantiallyinhibiting, slowing or reversing the progression of a condition,substantially ameliorating clinical or aesthetical symptoms of acondition or substantially preventing the appearance of clinical oraesthetical symptoms of a condition.

It is appreciated that certain features of the invention, which are, forclarity, described in the context of separate embodiments, may also beprovided in combination in a single embodiment. Conversely, variousfeatures of the invention, which are, for brevity, described in thecontext of a single embodiment, may also be provided separately or inany suitable subcombination or as suitable in any other describedembodiment of the invention. Certain features described in the contextof various embodiments are not to be considered essential features ofthose embodiments, unless the embodiment is inoperative without thoseelements.

What is claimed is:
 1. A method for ablating a target vein in a patient,comprising: providing an intravascular irritation element having a wovenmesh, said woven mesh is made of one or more memory shape wires and setto expand by regaining a geometry having a diameter that is greater thana diameter of a venous lumen of a target vein, said geometry limits thepenetration of said intravascular irritation element into the intima ofsaid venous lumen; inserting said intravascular irritation element intosaid venous lumen using a catheter mechanism; and irritating said targetvein by moving said intravascular irritation element in contact with aninner surface thereof so that a collapse of said target vein beingtriggered; wherein said woven mesh is a flexible mesh sized and shapedto expand so as to scratch venous walls of said target vein when saidintravascular irritation element is moved along said target vein.
 2. Themethod of claim 1, wherein said woven mesh is sized and shaped to expandso that during said moving said woven mesh continually bended againstvein passage surface of said venous lumen which limits its expanding. 3.The method of claim 1, wherein the woven mesh having a plurality ofmechanical irritating objects.
 4. The method of claim 1, wherein saidwoven mesh is a shape memory element having a regainable geometry,wherein said providing comprises providing said intravascular irritationelement in a collapsed state and said irritating comprises allowing saidshape memory element to expand toward said regainable geometry in saidvenous lumen.
 5. The method of claim 1, wherein said irritatingcomprises rotating said intravascular irritation element around alongitudinal axis of said target lumen.
 6. The method of claim 5,wherein said rotating is performed simultaneously with at least one ofpushing and pulling said intravascular irritation element along saidlongitudinal axis.
 7. The method of claim 3, wherein said irritatingcomprises maneuvering said intravascular irritation element so that atleast one of said mechanical irritating object being brushed againstsaid inner surface in a helical pattern.
 8. The method of claim 1,wherein said flexible mesh comprises a member of group consisting of aplurality of memory shape wires, plurality of coarse wires and aplurality of jagged wires.
 9. The method of claim 1, wherein saidflexible mesh is set to regain a shape of a cylinder having a diameterthat is greater than the diameter of the venous lumen of said targetvein when unbounded.
 10. An intrabody device for ablating a target veinin a patient, comprising: a shaft being insertable into a venous lumenof a target vein; an intravascular irritation element affixed at adistal end of said shaft and having a woven mesh, said woven mesh ismade of one or more memory shape wires to expand by regaining a geometryhaving a diameter that is greater than a diameter of said venous lumen;and wherein said intravascular irritation element is sized and shaped tobe moved in said venous lumen so that said woven mesh is in contact withan inner surface of said target vein; wherein said woven mesh is aflexible mesh is sized and shaped to expand so as to scratch venouswalls of said target vein when said intravascular irritation element ismoved along said target vein by regaining a geometry having a diametergreater than a diameter of said venous lumen such that when said wovenmesh is maneuvered in said venous lumen, said woven mesh continuallybended against vein passage surface of said venous lumen which limitsits expanding; wherein said geometry limits a penetration of saidintravascular irritation element into the intima of said lumen when saidwoven mesh continually bended against vein passage surface of saidvenous lumen.
 11. The intrabody device of claim 10, further comprisingan extraction channel positioned along said shaft to withdraw blood witha medical substance in the vein.
 12. The intrabody device of claim 10,wherein said woven mesh is weaved from a wire and having a plurality ofmechanical irritating objects protruding therefrom.
 13. The intrabodydevice of claim 10, further comprising a sheath covering at least saiddistal end, said intravascular irritation element having a collapsedstate for inserting said intravascular irritation element into saidsheath and an expanded state for brushing against said inner surface.14. The intrabody device of claim 10, wherein said woven mesh is aflexible mesh woven from a first wire made of a shape memory materialand a second wire having a plurality of mechanical irritating objectsaffixed thereto.
 15. The intrabody device of claim 10, furthercomprising a controller for simultaneously rotating said intravascularirritation element around a longitudinal axis of said target lumen andat least one of pushing said intravascular irritation element along saidlongitudinal axis and pulling said intravascular irritation elementalong said longitudinal axis.
 16. The intrabody device of claim 11,wherein said extraction channel is configured for performing saidwithdrawing while said intravascular irritation element beingmaneuvered.
 17. The intrabody device of claim 10, further comprising anexpandable filter element affixed at a distal end of said intravascularirritation element and configured for filtering blood during saidintravascular irritation element being maneuvered in said venous lumen.18. The intrabody device of claim 11, wherein said extraction channel isformed in the lumen between said shaft and a sheath covering said shaft.19. An intrabody device for ablating a target vein in a patient,comprising: a shaft being insertable into a venous lumen of a targetvein; and a flexible woven mesh made of one or more memory shape wiresand set to expand by regaining a geometry having a diameter that isgreater than a diameter of said venous lumen, wherein said geometrylimits a penetration of said flexible woven mesh into the intima of saidlumen when said woven mesh continually bended against vein passagesurface of said venous lumen; wherein said flexible mesh is sized andshaped to expand such that when said woven mesh is moved by said shaftalong said target vein, said woven mesh continually bended against veinpassage surface of said venous lumen which limits its expanding andscratches the venous walls of said target vein; wherein said woven meshis a flexible mesh and is sized and shaped to expand so as to scratchvenous walls of said target vein when said flexible woven mesh is movedalong said target vein.
 20. The intrabody device of claim 19, whereinthe woven mesh having a plurality of mechanical irritating objects.